Polyethylene glycol 1540 is a generic name for mixtures of condensation polymers of ethylene oxide and water, available in liquid form (polymers with average molecular weights between 200 and 700) or as waxy solids (average molecular weights above 1000); some are used as pharmaceutic aids, and p. glycol 3350 is used as a laxative. CAS: 25322-68-3. The volume of rectal epithelial mucus was quantified histologically following a single suppository treatment. Molecular weight:1300～1600. It was unchanged by suppositories of Witepsol H12; reduced significantly by suppositories of PEG 1540 1, 6 and 24 h post-treatment but increased after 48 h. Molecular formula: HO(CH2CH2O)nH. It occurs as a soft white or light yellow waxy solid
Properties:The relative density of 1.15. Flash point> 232 ℃ .
Polyethylene glycol 1540 is used in GC stationary liquid (maximum temperature 165 ℃ , solvent, acetone, chloroform, methylene chloride) and the separation of oxygenated nitrogen compounds.
Storage:Sealed in cool place. Confers slip and humectant properties to coatings. See poly(ethylene oxide) for higher molecular weights.
The terms poly(ethylene glycol) and poly(ethylene oxide) refer to polymers which are chemically identical. Polymer chains are hydroxyl-terminated at both ends. At all except the lowest molecular weights poly(ethylene glycol) has a broad molecular weight distribution ranging from ~ 0.5x to 1.5x the values shown.
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